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How do I create/buy a 0-9v LED Voltmeter? Answered

I am doing a school science fair project and I need to create/buy a LED Voltmeter. It will be hooked up to a DC motor that is connected to my bike. This DC motor is producing about 0-9v. This LED Voltmeter will be used to display how much power is going to be made.


You can use LM 3914 Dot/Bar Display Driver.
Calibrate display for 1-9 V.

  • IC pin 9 is dot/bar select (V+/V-).
3914battmon.giflm3914voltmeter, 1-8 Volt.jpg

Are you looking for a full digital readout, or a simple bar of LED's which light up with increasing voltage?